diff --git a/reactos/include/reactos/drivers/directx/dxeng.h b/reactos/include/reactos/drivers/directx/dxeng.h
index e473710c2d5..90353c376a1 100644
--- a/reactos/include/reactos/drivers/directx/dxeng.h
+++ b/reactos/include/reactos/drivers/directx/dxeng.h
@@ -84,6 +84,7 @@ DWORD STDCALL DxEngReferenceHdev(HDEV hdev);
 BOOLEAN STDCALL DxEngLockShareSem();
 BOOLEAN STDCALL DxEngUnlockShareSem();
 DWORD STDCALL DxEngScreenAccessCheck();
+BOOL STDCALL DxEngSetDCOwner(HGDIOBJ hObject, DWORD OwnerMask);
 
 /* prototypes are not done yet, I need gather all my notes
  * to make them correct
@@ -106,7 +107,6 @@ DWORD DxEngSpUnTearDownSprites(DWORD x1, DWORD x2, DWORD x3);
 DWORD DxEngSpSpritesVisible(DWORD x1);
 DWORD DxEngGetDesktopDC(DWORD x1, DWORD x2, DWORD x3);
 DWORD DxEngDeleteDC(DWORD x1, DWORD x2);
-DWORD DxEngSetDCOwner(DWORD x1, DWORD x2);
 DWORD DxEngSetDCState(DWORD x1, DWORD x2, DWORD x3);
 DWORD DxEngSelectBitmap(DWORD x1, DWORD x2);
 DWORD DxEngSetBitmapOwner(DWORD x1, DWORD x2);
diff --git a/reactos/include/reactos/win32k/ntgdihdl.h b/reactos/include/reactos/win32k/ntgdihdl.h
index b5abd9347e5..61f69a36cca 100644
--- a/reactos/include/reactos/win32k/ntgdihdl.h
+++ b/reactos/include/reactos/win32k/ntgdihdl.h
@@ -111,6 +111,14 @@
 #define GDI_OBJECT_GET_TYPE_INDEX(t) \
     ((t & GDI_HANDLE_BASETYPE_MASK) >> GDI_HANDLE_BASETYPE_SHIFT)
 
+/* Gdi Object Handle Managment Pid lock masking sets. */
+/* Ref: used with DxEngSetDCOwner */
+#define GDI_OBJ_HMGR_PUBLIC     0          // Public owner, Open access?
+#define GDI_OBJ_HMGR_POWNED     0x80000002 // Set to current owner.
+#define GDI_OBJ_HMGR_NONE       0x80000012 // No owner, Open access?
+#define GDI_OBJ_HMGR_RESTRICTED 0x80000022 // Restricted?
+
+
 /* DC OBJ Types */
 #define DC_TYPE_DIRECT 0  // normal device context
 #define DC_TYPE_MEMORY 1  // memory device context
diff --git a/reactos/subsystems/win32/win32k/ntddraw/dxeng.c b/reactos/subsystems/win32/win32k/ntddraw/dxeng.c
index 365db446cef..97b95ce8545 100644
--- a/reactos/subsystems/win32/win32k/ntddraw/dxeng.c
+++ b/reactos/subsystems/win32/win32k/ntddraw/dxeng.c
@@ -1,3 +1,4 @@
+
 /*
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel
@@ -722,7 +723,7 @@ BOOLEAN DxEngCleanDC(HDC hdc)
 /************************************************************************/
 /* DxEngSetDCOwner                                                      */
 /************************************************************************/
-DWORD DxEngSetDCOwner(DWORD x1, DWORD x2)
+BOOL STDCALL DxEngSetDCOwner(HGDIOBJ hObject, DWORD OwnerMask)
 {
     UNIMPLEMENTED;
     return FALSE;